What is the test for a superseding cause?

A party is entitled upon request to correct, nonargumentative jury instructions on every theory advanced by the party that is supported by substantial evidence. However, the trial court is not required to give instructions that are not correct statements of the law or that are incomplete or misleading. (Norman v. Life Care Centers of America, Inc. (2003) 107 Cal.App.4th 1233, 1242.)

A superseding cause is an act of a third party or other force that by its intervention prevents the actor from being liable for harm to another which his or her antecedent negligence is a substantial factor in bringing about. The doctrine requires more than mere negligence on the part of the intervening actor. The fact that the third person's intervening act is done in a negligent manner does not make it a superseding cause if a reasonable person, knowing the situation existing when the act of the third person is done, would not consider the act highly extraordinary, or if the act is a normal response to a situation created by the defendant's conduct and the manner in which the intervening act is done is not extraordinarily negligent. (Perez v. VAS S.P.A. (2010) 188 Cal.App.4th

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